To Diaphragm -OR- To Piston... that is the newbie question for a regulator

[olstykke]

Hi, I've only rented equipment in the past. I think most of them have been diagphram regulators.


Of the two dive shops, one is scubapro and one is aqualung.

One says pistons rulz... 15 minuts away the others say diaphragms are the way to go.

I know this is going to get alot of debate.

But this is my dilemma:

The scupapro guys says that the scubapro:

-- breaths easier
-- has a better warranty. As long as i maintain it every year, parts are included. If it breaks and I can prove that I maintianed it every year, scubapro will give me a replacement of equivalent perfomance level.

-- $15 a stage labor. 1st+2nd+octopus = 3x15 = 45

aqualung

--A little cheaper $50
-- similar warranty, only pay for labor... labor moreexpensive.
--DO not know about replacement option.

I've looked onlline, but do not know where I can get service for other manufacturers even if purchased from authorized dealer.



So diaphragm or piston?

Has anyone else dealt with scubpro and aqualung warranty?

Other manufactuers.


I don't have any equip yet except mask, fins and snorkel.

I''m also looking at computers. I might pose that question in another post, but the oceanic atom looks pretty good for price, options.

I am student with limited funds, but I'd rather buy quality and features now, instead of buying a sequence of upgrades and gear.

Thanks

 

[RTodd]

Hi, I've only rented equipment in the past. I think most of them have been diagphram regulators.

I don't have any equip yet except mask, fins and snorkel.

I am student with limited funds, but I'd rather buy quality and features now, instead of buying a sequence of upgrades and gear.

Thanks

First, in general a diaphragm regulator will last longer between "needed" services. So, I would go with a diaphragm reg. Personally, I really like the Apex regs. I can't assist you with any other brands because I have not found a need to look beyond apex.

I have probably a dozen scubapro regs that I use on stage bottles. (In a situation where the reg is more likely to be flooded, piston is generally a better choice.) Based on my primary criteria of, I don't want to have to overhaul the regs regularly, they suck. Scubapros, in general, need an annual maintenance because they start experiencing problems within a year. They do breath great, slightly better than the apex. They are also more prone to freeflow because of this. It is a very good reg but I would not recommend it as an open water reg. Lots of people use them though. If you decide you have to have the scubapro, have the tech set the initial IP as close to 120 as possible. This reduces freeflows and helps extend the service interval life with no discernable affect on performance.

 

[wedivebc]

Hi, I've only rented equipment in the past. I think most of them have been diagphram regulators.


Of the two dive shops, one is scubapro and one is aqualung.

One says pistons rulz... 15 minuts away the others say diaphragms are the way to go.

I know this is going to get alot of debate.

But this is my dilemma:

The scupapro guys says that the scubapro:

-- breaths easier
-- has a better warranty. As long as i maintain it every year, parts are included. If it breaks and I can prove that I maintianed it every year, scubapro will give me a replacement of equivalent perfomance level.

-- $15 a stage labor. 1st+2nd+octopus = 3x15 = 45

aqualung

--A little cheaper $50
-- similar warranty, only pay for labor... labor moreexpensive.
--DO not know about replacement option.

I've looked onlline, but do not know where I can get service for other manufacturers even if purchased from authorized dealer.



So diaphragm or piston?

Has anyone else dealt with scubpro and aqualung warranty?

Other manufactuers.


I don't have any equip yet except mask, fins and snorkel.

I''m also looking at computers. I might pose that question in another post, but the oceanic atom looks pretty good for price, options.

I am student with limited funds, but I'd rather buy quality and features now, instead of buying a sequence of upgrades and gear.

Thanks

I used to sell and service aqualung regs. I can't speak about scubapro but I never had to replace a reg. They were always repairable using normal rebuild parts. There are not many moving parts in a diaphram 1st stage so not much can go wrong.

 

[Rookie_J]

i like my Tusa reg.

 

[ScubaDadMiami]

Piston regulators allow whatever you are diving in to enter the first stage (unless you get a special kit to prevent this). This can lead to the need for more frequent service and other problems if things get inside the first stage like debris, sand, etc.

Piston regulators used to be somewhat better breathers. So, that was why so many hyped them. Also, there was a point where they were the ones that could be rigged for oxygen service. A big reason many went with Scubapro was that, in remote locations, they had parts available the world over.

Today, all top performers breathe well, piston or diaphram. There are other well known brands with parts available pretty much anywhere that one can find dive shops. There are more nitrox ready regulators out on the market. So, most of the reasons for the piston and Scubapro requirement no longer matter as much as before. Yet, Scubapro dealers continue to push their exclusiveness to lure buyers.

Scubapro makes a fine regulator. However, they will cut off their dealers (or at least they used to) if they find out that they are discounting their products. They try to build a mystique into their brand name to justify a higher price that I don't think is worth it anymore.

The last time I checked, Aqualung Lengend LX Supremes were the best breathers overall on the market, which was not terribly long ago. I have two sets of them and use them to regularly dive beyond 200 feet. I would buy them again without thinking twice.

 

[crpntr133]

Personally I wouldn't go with anything other than a diaphram. Of course you are asking a cold water diver which he would use.

 

[DA Aquamaster]

As a tech working on a variety of regulators (Scubapro, Dacor, Sherwood/Genesis, Tusa, USD Divers/Aqualung, ) I can tell you the "piston regs need service more often" argument is not valid.

A newer Mk 20 or 25 with large ambient chamber ports is easy to rinse and will not create any more problems than the average diaphragm reg. Internally, they are much simpler and warranty requirements aside, a piston first stage will normally go 4-5 years between service with proper care and cleaning. As far as numbers of dives between services, I put 160 dives on mine last year with no problems.

There is a myth floating around that diaphragm regs are by definition environmentally sealed, when in truth most are not. Some of the worst regs I see service wise are diaphragm regs as some diaphragm designs are very hard to rinse in the ambient chamber areas with resulting problems with excessive corrosion and mechanical issues even after 1 year intervals.

I don't think the piston/diaphragm issue has much impact on breathing performance with top end diaphragm regs, but lower performance diaphragm regs tend to have an excessive IP drop which effects breathing performance in higher demand situations. And by piston standards, even a top end diaphragm reg is only in the medium performance category.

Second stage performance has much more to do with the diver's perception of whether a reg is easy breathing. Personally, I like the upper end Aqualung regs like the Ledgend, but I still prefer SP second stages for their quality, performance potential and ease of tuning and servicing.

I also dive cold water almost exclusively and have not had issues with the Mk 25 freezing up but mileage varies on that issue. For cold water use the S600 second stage should not be your first choice and you would be better off with a G250 or even an R190 or R390.

I do agree though that SP needs to move away from their elitist marketing practices as they are counter productive and in reality, most SP dealers also carry another line of regulators anyway, so the approach rings very hollow if the diver notes all the other non SP regs in the display case.

Of course on the other hand, a subset of DIR/GUE divers tend to be just as elitist about Apeks regs no matter how bad a particular model may breathe since they are the current DIR/GUE darlings - a issue that is very political in nature.

But SB board members opinion's aside, your decision should be based more on

1) which dealer you feel more comfortable with, and
2) a test dive with each model of regulator, and
3) which reg you prefer.

 

[WaterDawg]

DA,

Would you say a diaphram reg that IS sealed can go longer w/o need of service? And what do some of the reg companies recomend as a service interval (in # of dives)?

 

[RTodd]

DA,

Would you say a diaphram reg that IS sealed can go longer w/o need of service? And what do some of the reg companies recomend as a service interval (in # of dives)?

In general, sealed diaphragm regs (the only kind I personally use) are capable of performing properly for much longer between service intervals. (I have some that have been in use over 5 years that have never been overhauled.) Sealed pistons don't work as well and unless things have changed are too messy to be worth it. Almost all of the reg manufacturers say 1 year. Most open water divers don't do it that often and those of us with dozens of regs want to avoid the hassle if not necessary. If you just have one open water reg, you should do it approximately yearly so the choice isn't as big of a deal.

 

[DA Aquamaster]

Would you say a diaphram reg that IS sealed can go longer w/o need of service?

Sealed diaphragms are definitely better at keeping dirt, water and contaminants out right up until the point where the seal leaks at which point they tend to let dirt, water and contaminants in and then trap them there. So I think they can potentially go longer, but only as long as everything stays intact. I know it is going to be a long day at the bench when I crack open a sealed diaphragm reg and discover water in there. New metal parts are usually required as the corrosion is usually extensive.

In my experience though diaphragm regs (sealed or otherwise) seem to suffer more of a performance decrease over longer service intervals as diaphragms compress, take a set, get stiff, etc. They are not less relaible or more prone to leak exactly, just less able to deliver top performance. This is just my opinion and not the 11th Comandment so dont read too much into it. There are also more o-rings in diaphragm regs and there are definitely more o-rings in HP areas of the reg so consequently there is also potentially more to go wrong.

And what do some of the reg companies recomend as a service interval (in # of dives)?

I have seen 50 and 100 dives thrown around as possible numbers. Scubapro sends us about 3 kits per year for every rental reg in the shop, so they obviouly feel regs that are used heavily should be serviced much more often than annually.

Sealed pistons don't work as well and unless things have changed are too messy to be worth it. Almost all of the reg manufacturers say 1 year. Most open water divers don't do it that often and those of us with dozens of regs want to avoid the hassle if not necessary. If you just have one open water reg, you should do it approximately yearly so the choice isn't as big of a deal.

I agree that older piston regs using silicone filled ambient chambers and boots can be messy to service and in cases where the boot design is poor can require some topping off of the silicone a few times during the season. But to put it in perspective the mess we are talking about is 2-3 minutes of wiping it out with a paper towel before doing the regular annual service cleaning and about 10 minutes on the other end of the annual service properly repacking the ambient chamber with new silicone or lube.

Even with the extra steps required to pack an ambient chamber, I can clean and service a balanced piston reg in far less time than I can a diaphragm reg as they are simpler with a lower parts count and are generally easier to disassemble and assemble.

And newer piston designs using other anti-freeze systems with much more open and easy to rinse ambient chambers are both non messy and very easy to service. There are also a couple of designs around using air filled chambers with one way check valves and in some cases a diaphragm and schrader valve arrangement to keep the ambient chamber at ambient pressure while keeping water out. They are very effective but again add complexity to an otherwise simple design and have the same issue as a sealed diaphragm reg if the diaphragm leaks.